One step at a time
Present Tense
Subject + To Be + Complement
I          am     a student
You    are     a student
He      is       a student
She    is       a student
It        is       a desk
We     are    students
You    are    students
They  are    students
Present Tense
Affirmative (contraction)
I'm               a student
You're         a student
He's             a student
She's           a student
It's               a desk
We're          students
You're        students
They're      students